Configuration method and controller

ABSTRACT

A configuration method and a controller are provided. The configuration method is applied to a network on which detection is performed by using the two-way active measurement protocol (TWAMP), and may include: receiving, by a controller, a request packet sent by an ingress network device, where the ingress network device is a network device through which a service flow flows into the network, and the request packet includes a destination IP address of the service flow; and determining, by the controller, based on the destination IP address, that the service flow is an X2 service flow, and sending configuration information for TWAMP detection to the ingress network device and an egress network device, where the egress network device is a network device through which the service flow flows out of the network.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of International Application No.PCT/CN2019/129772, filed on Dec. 30, 2019, which claims priority toChinese Patent Application No. 201811643001.2, filed on Dec. 29, 2018.The disclosures of the aforementioned applications are herebyincorporated by reference in their entireties.

TECHNICAL FIELD

Embodiments of this application relate to the field of communicationstechnologies, and in particular, to a configuration method and acontroller.

BACKGROUND

In a solution of a 5th generation mobile communications technology (5Gfor short) of an internet protocol radio access network (IP RAN forshort), a performance monitoring technology such as the two-way activemeasurement protocol (TWAMP for short) is used to measure performanceindicators such as a latency, a jitter, and a packet loss ratio of a 4thgeneration mobile communications technology (4G for short)/5G service.The performance indicators need to include performance indicators of twowireless services, namely, an S1 service and an X2 service.

A data service flow related to the X2 service may be referred to as anX2 service flow for short, and generally refers to a service flow from abase station to another base station. Theoretically, a physical distancebetween base stations is relatively short, and an X2 service flow mayexist between the base stations. Referring to FIG. 1 , a flow directionof a service flow between a base station (eNB) and another base stationis indicated by a dashed arrow. On the IP RAN, an ingress network deviceof a service flow may be a CSG, and an egress network device may beanother CSG. However, two CSGs to which base stations having an X2service therebetween are connected cannot be clearly learned of duringinitial service deployment, that is, two CSGs that have an X2 serviceflow therebetween cannot be determined. Consequently, two CSGs for whichTWAMP detection needs to be configured for an X2 service cannot belearned of. If TWAMP detection is deployed for any two CSGs, it isimpossible that there is an X2 service between a base station and allother base stations because of a limited quantity of neighboring basestations of the base station. Therefore, a CSG has the X2 service withonly a small quantity of CSGs, but does not have the X2 service with amajority of CSGs. Therefore, if the TWAMP detection is deployed for anytwo CSGs, there are a large quantity of redundant and invalidconfigurations. In addition, a TWAMP capacity of the CSG is limited, andthe redundant configurations pose a challenge to a device capacity.

SUMMARY

A technical problem to be resolved in embodiments of this application isto provide a configuration method and a controller based on TWAMPdetection, to resolve a problem that TWAMP detection cannot beaccurately configured for an X2 service, thereby improving efficiency ofthe TWAMP detection.

According to a first aspect, an embodiment of this application providesa configuration method, applied to a network on which detection isperformed by using the two-way active measurement protocol TWAMP. Themethod may include:

-   -   A controller receives a request packet sent by an ingress        network device, where the ingress network device is a network        device through which a service flow flows into the network, and        the request packet includes a destination IP address of the        service flow; and    -   the controller determines, based on the destination IP address,        that the service flow is an X2 service flow, and sends        configuration information for TWAMP detection to the ingress        network device and an egress network device, where the egress        network device is a network device through which the service        flow flows out of the network.

The controller determines, based on the destination IP address of theservice flow by identifying information about the ingress network deviceand the egress network device of the service flow, whether the serviceflow is a correct X2 service flow. In this way, the configurationinformation for the TWAMP detection can be automatically sent based oninformation such as addresses of interfaces, of the ingress networkdevice and egress network device, bound to a VRF, thereby improvingsystem detection efficiency and implementing TWAMP detection deploymentfor services in batches.

In a possible implementation, that the controller determines, based onthe destination IP address, that the service flow is an X2 service flowincludes:

-   -   The controller searches for, based on the destination IP        address, an egress device and a private network interface that        correspond to the destination IP address; and    -   the controller determines that the service flow is the X2        service flow, if the controller determines that the found egress        device and the found private network interface are respectively        an egress device and a private network interface that are        obtained through mask matching.

The X2 service flow is identified through mask matching, which isconvenient and fast and efficient.

In a possible implementation, that the controller sends configurationinformation for TWAMP detection to the ingress network device and theegress network device includes:

-   -   The controller forwards the request packet to the egress network        device;    -   when the egress network device determines that the destination        IP address corresponds to a virtual link VLINK route or an        address resolution protocol ARP or a static route that is of the        egress network device, the controller receives a response packet        sent by the egress network device;    -   the controller forwards the response packet to the ingress        network device; and    -   the controller separately sends the configuration information        for the TWAMP detection to the ingress network device and the        egress network device.

In a possible implementation, the request packet, the response packet,and a configuration packet that carries the configuration informationuse a same packet format, and the packet format includes a role field, amessage type field, a response value field, a source IP address field ofthe service flow, and a destination IP address field of the serviceflow, where

-   -   the role field is used to indicate a role of a device sending a        packet, and the device role includes the ingress network device,        the controller, and the egress network device;    -   the message type field is used to indicate a message type, and        the message type includes the request packet, the response        packet, and the configuration packet;    -   the response value field is used to indicate whether the service        flow is the X2 service flow, and is valid when a value of the        message type field indicates a response packet;    -   the source IP address field of the service flow is used to        indicate a source IP address of the service flow; and    -   the destination IP address field of the service flow is used to        indicate the destination IP address of the service flow.

According to a second aspect, an embodiment of this application providesa configuration method, applied to a network on which detection isperformed by using the two-way active measurement protocol TWAMP. Themethod may include:

-   -   After a traffic analyzer collects an ingress service flow of a        first device and an egress service flow of a second device for        analysis, and determines that the first device is an ingress        network device through which a service flow flows into the        network, and that the second device is an egress network device        through which the service flow flows out of the network, a        controller receives a request packet sent by the traffic        analyzer, where the request packet includes a first identifier        and a first interface of the ingress network device, a second        identifier and a second interface of the egress network device,        and a source IP address and a destination IP address of the        service flow; and    -   the controller determines, based on the information in the        request packet, that the service flow is an X2 service flow, and        sends configuration information for TWAMP detection to the        ingress network device and the egress network device.

In a possible implementation, that the controller determines, based onthe information in the request packet, that the service flow is an X2service flow includes:

-   -   The controller determines that the ingress network device and        the egress network device are bound to a same routing forwarding        table VRF;    -   the controller indicates the ingress network device to determine        whether the source IP address corresponds to a VLINK route or an        ARP or a static route that is on the first interface, and        indicates the egress network device to determine whether the        destination IP address corresponds to a virtual link VLINK route        or an address resolution protocol ARP or a static route that is        on the second interface;    -   when the ingress network device determines that the source IP        address corresponds to the virtual link VLINK route or the        address resolution protocol ARP or the static route that is on        the first interface, the controller receives a first response        packet sent by the egress network device;    -   when the egress network device determines that the destination        IP address corresponds to the virtual link VLINK route or the        address resolution protocol ARP or the static route that is on        the second interface, the controller receives a second response        packet sent by the egress network device; and    -   the controller determines that the service flow is the X2        service flow.

In a possible implementation, the request packet, the response packet,and a configuration packet that carries the configuration informationuse a same packet format, and the packet format includes a role field, amessage type field, a response value field, a source IP address field ofthe service flow, and a destination IP address field of the serviceflow, where

-   -   the role field is used to indicate a role of a device sending a        packet, and the device role includes the ingress device, the        controller, and the egress device;    -   the message type field is used to indicate a message type, and        the message type includes the request packet, the response        packet, and the configuration packet;    -   the response value field is used to indicate whether the service        flow is the X2 service flow, and is valid when a value of the        message type field indicates a response packet;    -   the source IP address field of the service flow is used to        indicate the source IP address of the service flow; and    -   the destination IP address field of the service flow is used to        indicate the destination IP address of the service flow.

According to a third aspect, an embodiment of this application providesa controller. The controller may include:

-   -   a transceiver unit, configured to receive a request packet sent        by an ingress network device, where the ingress network device        is a network device through which a service flow flows into the        network, and the request packet includes a destination IP        address of the service flow; and    -   a processing unit, configured to: determine, based on the        destination IP address, that the service flow is an X2 service        flow, and indicate the transceiver unit to send configuration        information for TWAMP detection to the ingress network device        and an egress network device, where the egress network device is        a network device through which the service flow flows out of the        network.

In a possible implementation, the processing unit is specificallyconfigured to:

-   -   search for, based on the destination IP address, an egress        device and a private network interface that correspond to the        destination IP address; and    -   determine that the service flow is the X2 service flow, if the        found egress device and the found private network interface are        respectively an egress device and a private network interface        that are obtained through mask matching.

In a possible implementation, the transceiver unit is specificallyconfigured to:

-   -   forward the request packet to the egress network device;    -   when the egress network device determines that the destination        IP address corresponds to a virtual link VLINK route or an        address resolution protocol ARP or a static route that is of the        egress network device, receive a response packet sent by the        egress network device;    -   forward the response packet to the ingress network device; and    -   separately send the configuration information for the TWAMP        detection to the ingress network device and the egress network        device.

In a possible implementation, the request packet, the response packet,and a configuration packet that carries the configuration informationuse a same packet format, and the packet format includes a role field, amessage type field, a response value field, a source IP address field ofthe service flow, and a destination IP address field of the serviceflow, where

-   -   the role field is used to indicate a role of a device sending a        packet, and the device role includes the ingress network device,        the controller, and the egress network device;    -   the message type field is used to indicate a message type, and        the message type includes the request packet, the response        packet, and the configuration packet;    -   the response value field is used to indicate whether the service        flow is the X2 service flow, and is valid when a value of the        message type field indicates a response packet;    -   the source IP address field of the service flow is used to        indicate a source IP address of the service flow; and    -   the destination IP address field of the service flow is used to        indicate the destination IP address of the service flow.

According to a fourth aspect, an embodiment of this application providesa controller. The controller may include:

-   -   a transceiver unit, configured to: after a traffic analyzer        collects an ingress service flow of a first device and an egress        service flow of a second device for analysis, and determines        that the first device is an ingress network device through which        a service flow flows into the network, and that the second        device is an egress network device through which the service        flow flows out of the network, receive a request packet sent by        the traffic analyzer, where the request packet includes a first        identifier and a first interface of the ingress network device,        a second identifier and a second interface of the egress network        device, and a source IP address and a destination IP address of        the service flow; and    -   a processing unit, configured to: determine, based on the        information in the request packet, that the service flow is an        X2 service flow, and send configuration information for TWAMP        detection to the ingress network device and the egress network        device.

In a possible implementation, the processing unit is specificallyconfigured to:

-   -   determine that the ingress network device and the egress network        device are bound to a same routing forwarding table VRF; and    -   indicate the ingress network device to determine whether the        source IP address corresponds to a VLINK route or an ARP or a        static route that is on the first interface, and indicate the        egress network device to determine whether the destination IP        address corresponds to a virtual link VLINK route or an address        resolution protocol ARP or a static route that is on the second        interface;    -   when the ingress network device determines that the source IP        address corresponds to the virtual link VLINK route or the        address resolution protocol ARP or the static route that is on        the first interface, the transceiver unit is further configured        to receive a first response packet sent by the egress network        device;    -   when the egress network device determines that the destination        IP address corresponds to the virtual link VLINK route or the        address resolution protocol ARP or the static route that is on        the second interface, the transceiver unit is further configured        to receive a second response packet sent by the egress network        device; and    -   the processing unit is further configured to determine that the        service flow is the X2 service flow.

In a possible implementation, the request packet, the response packet,and a configuration packet that carries the configuration informationuse a same packet format, and the packet format includes a role field, amessage type field, a response value field, a source IP address field ofthe service flow, and a destination IP address field of the serviceflow, where

-   -   the role field is used to indicate a role of a device sending a        packet, and the device role includes the ingress device, the        controller, and the egress device;    -   the message type field is used to indicate a message type, and        the message type includes the request packet, the response        packet, and the configuration packet;    -   the response value field is used to indicate whether the service        flow is the X2 service flow, and is valid when a value of the        message type field indicates a response packet;    -   the source IP address field of the service flow is used to        indicate the source IP address of the service flow; and    -   the destination IP address field of the service flow is used to        indicate the destination IP address of the service flow.

According to a fifth aspect, an embodiment of this application providesa controller. The controller may include:

-   -   a processor and a memory, where the processor is connected to        the memory, the memory is configured to store a computer        instruction, and the processor is configured to invoke the        computer instruction stored in the memory, to perform the steps        in any one of the first aspect, the second aspect, the        implementations of the first aspect, or the implementations of        the second aspect in the embodiments of this application.

According to a sixth aspect, an embodiment of this application providesa computer-readable storage medium. The computer-readable storage mediumstores an instruction, and when the instruction is run on a computer,the method according to any one of the first aspect, the second aspect,the implementations of the first aspect, or the implementations of thesecond aspect is implemented.

BRIEF DESCRIPTION OF DRAWINGS

To describe the technical solutions in the embodiments of thisapplication or in the background more clearly, the following describesthe accompanying drawings used in the embodiments of this application orthe background.

FIG. 1 is a schematic reference diagram of an X2 service flow path in anIP RAN system architecture according to an embodiment of thisapplication;

FIG. 2 is a schematic flowchart of a configuration method according toan embodiment of this application;

FIG. 3A and FIG. 3B are a schematic flowchart of another configurationmethod according to an embodiment of this application;

FIG. 4 is a schematic flowchart of still another configuration methodaccording to an embodiment of this application;

FIG. 5A and FIG. 5B are a schematic flowchart of still anotherconfiguration method according to an embodiment of this application;

FIG. 6 is a schematic composition diagram of a controller according toan embodiment of this application; and

FIG. 7 is a schematic composition diagram of another controlleraccording to an embodiment of this application.

DESCRIPTION OF EMBODIMENTS

The following describes the embodiments of this application withreference to the accompanying drawings in the embodiments of thisapplication.

The terms “comprising”, “including”, or any other variations thereof inthe specification, the claims, and the accompanying drawings of thisapplication, are intended to cover a non-exclusive inclusion. Forexample, a process, a method, a system, a product, or a device thatincludes a series of steps or units is not limited to the listed stepsor units, but optionally further includes an unlisted step or unit, oroptionally further includes another inherent step or unit of theprocess, the method, the product, or the device.

This application may be applied to an IP RAN. The network includes anetwork device. The network device performs a routing forwardingfunction and may be a router, a switch, a forwarder, or the like. Therouter, the switch, and the forwarder may be physical devices, or may bevirtual devices (for example, a virtual server, a virtual router, avirtual switch, or a virtual forwarder) implemented based on avirtualization technology. Depending on a location and a role of anetwork device deployed on the network, the network device may also bereferred to as a cell site gateway (CSG for short), an access servicegateway (ASG for short), a route reflector (RR for short), a radionetwork controller site gateway (RSG), or the like. FIG. 1 is aschematic reference diagram of an X2 service flow path in an IP RANsystem architecture. The architecture shown in FIG. 1 includes basestations (eNB), CSGs, ASGs, RRs, RSGs, and the like.

The CSG is connected to the eNB, and the RSG is connected to an EPC (notshown in FIG. 1 ). The ASG may be configured to connect a core layer andan aggregation layer, and the RR may be configured to connect the ASGand the RSG or another RR. There is an S1 service flow between a CSG andan RSG. A flow of an S1 service may be referred to as an S1 service flowfor short, and generally refers to a service flow from a base station toan evolved packet core (EPC for short) device. On an IP RAN, an ingressnetwork device of the service flow may be a CSG, and an egress networkdevice may be an RSG (the CSG is connected to a base station, and theRSG is connected to a base station controller). Because there is the S1service flow between the CSG and the RSG, TWAMP detection for the S1service can be configured for all CSGs and all RSGs. It is not clearwhether there is an X2 service flow between the CSGs. A case in whichthere is the X2 service flow between different CSGs includes but is notlimited to the following:

-   -   (1) There is the X2 service flow between CSGs on a same access        ring, such as a CSG 1 and a CSG 2 in FIG. 1 .    -   (2) There is the X2 service flow between CSGs on different        access rings connected to a same ASG, such as a CSG 1 to a CSG 4        in FIG. 1 .    -   (3) There is the X2 service flow between CSGs on different        access rings connected to different ASGs, such as a CSG 2 and a        CSG 3 in FIG. 1 .

A virtual private network (VPN for short) and a public network tunneldesign in an IP RAN solution can ensure correct forwarding of the X2service flow in the foregoing three scenarios. However, two CSGs towhich base stations having an X2 service therebetween are connectedcannot be clearly learned of during initial service deployment, that is,two CSGs that have an X2 service flow therebetween cannot be determined.Consequently, two CSGs for which TWAMP detection needs to be configuredfor the X2 service cannot be learned of, and a plan cannot be made inadvance. In addition, in the 3rd generation mobile communicationstechnology (3G for short) 3G/4G era, traffic of the X2 service accountsfor a relatively small proportion, approximately, 13%. However, aproportion of X2 service traffic between two base stations is higher inthe 5G era and even subsequent eras with higher-level communicationstechnologies. Therefore, performance detection for the X2 service isrequired. In the embodiments of this application, a normal X2 serviceflow can be identified through flow identification and deviceidentification, and an ingress device and an egress device of theservice flow on the IP RAN are identified and confirmed. Then,configuration information for the TWAMP detection may be automaticallysent based on information such as IP address of interfaces, of theingress device and the egress device, bound to a routing forwardingtable (VRF for short). The following problems on the IP RAN areresolved: Base stations that have the X2 service therebetween cannot beaccurately learned of when the TWAMP detection is deployed for a 5Gservice, and the TWAMP detection cannot be deployed on the entirenetwork for all the base stations. In this way, planning-free andautomatic TWAMP deployment is implemented.

The following describes in detail configuration methods in thisapplication with reference to FIG. 2 to FIG. 5B. The configurationmethods in embodiments may be applied to a network on which detection isperformed by using the TWAMP. For ease of description, in all theembodiments, identification of an X2 service flow and configuration ofTWAMP detection are described. It should be noted that identification ofan S1 service flow and the configuration of the TWAMP detection may alsobe performed by using the methods described in the embodiments of thisapplication. Details are not described in the embodiments of thisapplication.

FIG. 2 is a schematic flowchart of a configuration method according toan embodiment of this application. The following steps are specificallyincluded.

S201. A controller receives a request packet sent by an ingress networkdevice.

The controller may be a controller device of a network manager or anetwork cloud engine-IP (NCE-IP for short). The ingress network deviceand an egress network device described below may be entities, virtualrouter devices, virtual switch devices, virtual forwarder devices, orthe like.

Optionally, the request packet includes a destination IP address of aservice flow.

A source IP address of an IP packet corresponding to the service flow isan address of a source base station, and the destination IP address canbe found from a VRF table to implement normal forwarding of the IPpacket.

S202. The controller determines, based on the destination IP address,whether the service flow is an X2 service flow; and if yes, performsstep S203; otherwise, performs step S204.

S203. The controller sends configuration information for TWAMP detectionto the ingress network device and the egress network device.

S204. Determine that the service flow is an unauthorized service flow.

In this embodiment of this application, the controller determines, basedon the destination IP address of the service flow by identifyinginformation about the ingress network device and the egress networkdevice of the service flow, whether the service flow is a correct X2service flow. In this way, the configuration information for the TWAMPdetection can be automatically sent based on information such asaddresses of interfaces, of the ingress network device and egressnetwork device, bound to a VRF, thereby improving system detectionefficiency and implementing TWAMP detection deployment for services inbatches.

FIG. 3A and FIG. 3B are a schematic flowchart of another configurationmethod according to an embodiment of this application. In thisembodiment, the method includes the following steps.

S301. An ingress network device monitors a service flow, and records adestination IP address of the service flow.

Optionally, if a TWAMP detection configuration corresponding to thedestination IP address already exists, the TWAMP detection configurationmay be ignored, and no subsequent processing is performed. Otherwise, asubsequent step may continue to be performed.

S302. If the destination IP address is not an IP address of a basestation or an EPC connected to another interface, of the ingress networkdevice, bound to a VRF, the ingress network device sends a requestpacket to a controller.

Optionally, if the destination IP address is the IP address of the basestation connected to the another interface, of the ingress networkdevice, bound to the VRF, it indicates that one CSG is connected to twobase stations, and there is an X2 service flow between the two basestations. In this case, TWAMP detection is not required.

If the destination IP address is the IP address of the EPC connected tothe another interface, of the ingress network device, bound to the VRF,it indicates that an RSG is connected to one base station nearby whenbeing connected to the EPC, and there is an S1 service flow. In thiscase, the TWAMP detection is not required either. Therefore, in twoforegoing cases, the TWAMP detection configuration may be ignored and nosubsequent processing is performed. Otherwise, a subsequent step maycontinue to be performed.

S303. The controller parses the request packet to obtain the destinationIP address, and searches for an egress network device and a privatenetwork interface that correspond to the destination IP address.

S304. If the found egress network device and the found private networkinterface are respectively an egress network device and a privatenetwork interface that are obtained through mask matching, thecontroller determines that the service flow is an X2 service flow,re-encapsulates the request packet, and forwards the request packet tothe egress network device.

Optionally, if the found egress network device and the found privatenetwork interface are not respectively the egress network device and theprivate network interface that are obtained through mask matching, thecontroller determines that the service flow is an unauthorized serviceflow, and performs no subsequent processing. A mask known to thecontroller usually corresponds to a segment of an IP address. If thedestination IP address is not in the segment of the IP address, itindicates the destination IP address does not match the mask. If thedestination IP address is in the segment of the IP address, it indicatesthat the IP address matches the mask.

S305. The egress network device parses the request packet to obtain thedestination IP address.

Then, the egress network device determines whether the destination IPaddress is an IP address of a base station corresponding to aninterface, of the egress network device, bound to the VRF. (If theservice flow is an S1 service flow, the service flow corresponds to theEPC.) A specific manner may be determined in a manner of step S306.

S306. When the egress network device determines that the destination IPaddress corresponds to a virtual link VLINK route or an ARP or a staticroute that is of the egress network device, the egress network devicesends a response packet to the controller.

If none of foregoing conditions are met, the controller determines thatthe service flow is an unauthorized service flow, and performs nosubsequent processing.

S307. The controller forwards the response packet to the ingress networkdevice.

S308. The controller sends configuration information for the TWAMPdetection to the ingress network device.

S309. The controller sends the configuration information for the TWAMPdetection to the egress network device.

The configuration information for the TWAMP detection may include but isnot limited to: a device that provides a TWAMP service, a port numberused during detection, a packet sending parameter, and an IP addressused during detection. More specifically, for a parameter configurationrule of the TWAMP detection, an ingress network device CSG of an X2service may be used as the TWAMP server, and an ingress network deviceRSG of an S1 service may be used as the TWAMP server. The port numbermay be a number of an unused port on each device. The packet sendingparameter may be sent based on a predetermined default value. IPaddresses are private IP addresses of devices at two ends.

Optionally, in this embodiment, the request packet, the response packet,and a configuration packet that carries the configuration informationmay use a same packet format or different packet formats.

When the same packet format is used, the packet format may include butis not limited to a version field, a role field, a message type field, aresponse value field, and a source IP address (Stream source IP) fieldof the service flow, a destination IP address (Stream destination IP)field of the service flow, and a virtual private network VPN identifier(VPN target) field.

The version number field is used to indicate a version of the packetformat. For example, a value 1 indicates a version 1.

The role field is used to indicate a role of a device sending a packet,and the device role includes the ingress network device, the controller,and the egress network device. For example, a value of the ingressnetwork device may be 0, a value of the controller may be 1, and a valueof the egress network device may be 2.

The message type field is used to indicate a message type, and themessage type includes the request packet, the response packet, and theconfiguration packet. For example, a value of the request packet is 0, avalue of the response packet is 1, and a value of the configurationpacket is 2.

The response value field is used to indicate whether the service flow isthe X2 service flow, and is valid when a value of the message type fieldindicates a response packet; and a default value is 0. This parameter isvalid only when Message type is set to 1. A value of this parameter is 1for the X2 service flow and is not 1 for an unauthorized service flow.

The source IP address field of the service flow is used to indicate asource IP address of the service flow.

The destination IP address field of the service flow is used to indicatethe destination IP address of the service flow.

The VPN identifier field is used to identify a private network VPN.

For a transmission protocol of the foregoing packet, the transmissioncontrol protocol (TCP) may be used at a transport layer. For an IPpacket of an outer layer of the packet, a source address or adestination address may be an IP address of a local loopback 0 interfaceof a device or an IP address of an NCE-IP.

FIG. 4 is a schematic flowchart of still another configuration methodaccording to an embodiment of this application. In this embodiment, themethod may include the following steps.

S401. After a traffic analyzer collects an ingress service flow of afirst device and an egress service flow of a second device for analysis,and determines that the first device is an ingress network device of aservice flow and that the second device is an egress network device ofthe service flow, a controller receives a request packet sent by thetraffic analyzer.

The request packet includes a first identifier and a first interface ofthe ingress network device, a second identifier and a second interfaceof the egress network device, and a source IP address and a destinationIP address of the service flow.

S402. The controller determines, based on the information in the requestpacket, whether the service flow is an X2 service flow; and if yes,performs step S403; otherwise, performs step S404.

S403. The controller sends configuration information for TWAMP detectionto the ingress network device and the egress network device.

S404. Determine that the service flow is an unauthorized service flow.

In this embodiment of this application, service flow sampling may bedeployed on interfaces, of all routers, bound to VRFs, and the trafficanalyzer collects source IP addresses and destination IP addresses ofsampled service flows on all the devices for analysis, to determine twodevices that have the service flow therebetween and submit a determiningresult to the controller to further confirm whether the service flow isthe X2 service flow. Finally, the controller automatically sends theconfiguration information for the TWAMP detection based on configurationinformation (including information about an interface IP address, anavailable port, or the like) of the ingress network device and theegress network device of the service flow, to reduce costs and implementbatch service deployment in an automatic service flow identificationmanner that is triggered by the service flow.

FIG. 5A and FIG. 5B are a schematic flowchart of still anotherconfiguration method according to an embodiment of this application. Inthis embodiment, the method includes the following steps.

S501. A traffic analyzer monitors a service flow, and collects aningress service flow of a first device and an egress service flow of asecond device for analysis.

It should be noted that, in this embodiment of this application, serviceflow sampling may be deployed on interfaces, of all routing devices,bound to VRFs, and the traffic analyzer collects source IP addresses anddestination IP addresses of sampled service flows on all the routingdevices for analysis, to analyze two routing devices that have theservice flow therebetween. For ease of description, two devices, namely,the first device and the second device, are used for description herein.If there are a plurality of devices, the devices are paired foranalysis. Details are not described herein.

S502. If a source IP address and a destination IP address of the ingressservice flow of the first device are respectively the same as a sourceIP address and a destination IP address of the egress service flow ofthe second device, the traffic analyzer determines that the first deviceand the second device respectively are an ingress network device and anegress network device of the service flow, and sends a request packet toa controller.

The traffic analyzer can determine the ingress network device and egressnetwork device of the service flow. However, usually, the trafficanalyzer cannot ensure whether the service flow is an unauthorizedservice flow such as attack traffic, or whether two service flows areservice flows with a same source or destination IP address but differentVRF. Therefore, the controller needs to perform further identificationand confirmation.

Optionally, if TWAMP detection configurations corresponding to thesource IP address and the destination IP address already exist, theTWAMP detection configurations may be ignored, and no subsequentprocessing is performed. Otherwise, a subsequent step may continue to beperformed.

S503. The controller parses the request packet, and determines whetherthe ingress network device and the egress network device are bound to asame routing forwarding table VRF.

S504. If the ingress network device and the egress network device arebound to the same VRF, the controller forwards the request packet to theingress network device and the egress network device.

Optionally, if the ingress network device and the egress network deviceare not bound to the same VRF, the controller determines that thetraffic analyzer performs analysis incorrectly, and may notify thetraffic analyzer of the determining result.

S505. The ingress network device parses the request packet to obtain thesource IP address and information about a first interface.

S506. When the ingress network device determines that the source IPaddress corresponds to a VLINK route or an ARP or a static route that ison the first interface, the ingress network device sends a firstresponse packet to the controller.

Optionally, if none of all foregoing conditions are met, an errorindication may be returned to the controller, to notify the controllerthat the service flow is an unauthorized service flow.

S507. The egress network device parses the request packet to obtain thedestination IP address and information about a second interface.

S508. When the egress network device determines that the destination IPaddress corresponds to a VLINK route or an ARP or a static route that ison the second interface, the egress network device sends a secondresponse packet to the controller.

Optionally, if none of all foregoing conditions are met, the errorindication may be returned to the controller, to notify the controllerthat the service flow is the unauthorized service flow.

S509. The controller determines that the service flow is an X2 serviceflow.

S510. The controller sends configuration information for TWAMP detectionto the ingress network device.

S511. The controller sends the configuration information for the TWAMPdetection to the egress network device.

S512. The controller returns a service flow identifier to the trafficanalyzer, to identify the service flow as a known service flow.

For the known service flow, the traffic analyzer does not need toanalyze the known service flow within a specified period.

For descriptions of a configuration rule, a packet format, a packettransmission protocol, or the like of the configuration information forthe TWAMP detection, refer to the descriptions in the embodiment shownin FIG. 3A and FIG. 3B. Details are not described herein again.

FIG. 6 is a schematic composition diagram of a controller according toan embodiment of this application. The controller may include:

-   -   a transceiver unit 100, configured to receive a request packet        sent by an ingress network device, where the ingress network        device is a network device through which a service flow flows        into the network, and the request packet includes a destination        IP address of the service flow; and    -   a processing unit 200, configured to: determine, based on the        destination IP address, that the service flow is an X2 service        flow, and indicate the transceiver unit 100 to send        configuration information for TWAMP detection to the ingress        network device and an egress network device, where the egress        network device is a network device through which the service        flow flows out of the network.

The processing unit 200 is specifically configured to:

-   -   search for, based on the destination IP address, an egress        device and a private network interface that correspond to the        destination IP address; and    -   determine that the service flow is the X2 service flow, if the        found egress device and the found private network interface are        respectively an egress device and a private network interface        that are obtained through mask matching.

Optionally, if the service flow is the X2 service flow, the transceiverunit 100 is specifically configured to:

-   -   forward the request packet to the egress network device;    -   when the egress network device determines that the destination        IP address corresponds to a virtual link VLINK route or an        address resolution protocol ARP or a static route that is of the        egress network device, receive a response packet sent by the        egress network device;    -   forward the response packet to the ingress network device; and    -   separately send the configuration information for the TWAMP        detection to the ingress network device and the egress network        device.

Optionally, the request packet, the response packet, and a configurationpacket that carries the configuration information use a same packetformat.

Optionally, the packet format includes a version field, a role field, amessage type field, a response value field, a source IP address field ofthe service flow, a destination IP address field of the service flow,and a virtual private network VPN identifier field, where the versionfield is used to indicate a version of the packet format;

-   -   the role field is used to indicate a role of a device sending a        packet, and the device role includes the ingress network device,        the controller, and the egress network device;    -   the message type field is used to indicate a message type, and        the message type includes the request packet, the response        packet, and the configuration packet;    -   the response value field is used to indicate whether the service        flow is the X2 service flow, and is valid when a value of the        message type field indicates a response packet;    -   the source IP address field of the service flow is used to        indicate a source IP address of the service flow;    -   the destination IP address field of the service flow is used to        indicate the destination IP address of the service flow; and    -   the VPN identifier field is used to identify a private network        VPN.

In another implementation, a controller may include:

-   -   a transceiver unit 100, configured to: after a traffic analyzer        collects an ingress service flow of a first device and an egress        service flow of a second device for analysis, and determines        that the first device is an ingress network device through which        a service flow flows into a network, and that the second device        is an egress network device through which the service flow flows        out of the network, receive a request packet sent by the traffic        analyzer, where the request packet includes a first identifier        and a first interface of the ingress network device, a second        identifier and a second interface of the egress network device,        and a source IP address and a destination IP address of the        service flow; and    -   a processing unit 200, configured to: determine, based on the        information in the request packet, that the service flow is an        X2 service flow, and indicate the transceiver unit 100 to send        configuration information for TWAMP detection to the ingress        network device and the egress network device.

Optionally, the processing unit 200 is specifically configured to:

-   -   determine that the ingress network device and the egress network        device are bound to a same routing forwarding table VRF; and    -   indicate the ingress network device to determine whether the        source IP address corresponds to a VLINK route or an ARP or a        static route that is on the first interface, and indicate the        egress network device to determine whether the destination IP        address corresponds to a virtual link VLINK route or an address        resolution protocol ARP or a static route that is on the second        interface;    -   when the ingress network device determines that the source IP        address corresponds to the virtual link VLINK route or the        address resolution protocol ARP or the static route that is on        the first interface, the transceiver unit 100 is further        configured to receive a first response packet sent by the egress        network device;    -   when the egress network device determines that the destination        IP address corresponds to the virtual link VLINK route or the        address resolution protocol ARP or the static route that is on        the second interface, the transceiver unit 100 is further        configured to receive a second response packet sent by the        egress network device; and    -   the processing unit 200 is further configured to determine that        the service flow is the X2 service flow.

Optionally, the request packet, the response packet, and a configurationpacket that carries the configuration information use a same packetformat.

Optionally, the packet format includes a version field, a role field, amessage type field, a response value field, a source IP address field ofthe service flow, a destination IP address field of the service flow,and a virtual private network VPN identifier field, where

-   -   the version field is used to indicate a version of the packet        format;    -   the role field is used to indicate a role of a device sending a        packet, and the device role includes the ingress network device,        the controller, and the egress network device;    -   the message type field is used to indicate a message type, and        the message type includes the request packet, the response        packet, and the configuration packet;    -   the response value field is used to indicate whether the service        flow is the X2 service flow, and is valid when a value of the        message type field indicates a response packet;    -   the source IP address field of the service flow is used to        indicate the source IP address of the service flow;    -   the destination IP address field of the service flow is used to        indicate the destination IP address of the service flow; and    -   the VPN identifier field is used to identify a private network        VPN.

For concepts, explanations, detailed descriptions, and other steps ofthe controller that are related to the technical solutions provided inthe embodiments of this application, refer to descriptions of thecontent in the foregoing method embodiments. Details are not describedherein again.

FIG. 7 is a schematic composition diagram of another controlleraccording to an embodiment of this application. As shown in FIG. 7 , thecontroller may include a processor 110 and a memory 120. The processor110 is connected to the memory 120. The memory 120 is configured tostore an instruction. The processor 110 is configured to execute theinstruction stored in the memory 120, to implement the steps in themethods corresponding to FIG. 2 to FIG. 5B.

Further, the controller may further include a transceiver 130. Theprocessor 110, the memory 120, and the transceiver 130 are connected toeach other.

The processor 110 is configured to execute the instruction stored in thememory 120, to control the transceiver 130 to receive a signal andcontrol the transceiver 130 to send a signal, to complete the stepsperformed by the controller in the foregoing method. The transceivers130 may be same physical entities or different physical entities. Ifbeing same physical entities, the physical entities may be collectivelyreferred to as the transceiver 130, and if being different physicalentities, the physical entities are referred to as a receiver and atransmitter respectively. The memory 120 may be integrated into theprocessor 110, or may be separated from the processor 110.

In an implementation, it may be considered that a function of thetransceiver unit 130 is implemented by using a transceiver circuit or aspecial-purpose transceiver chip. It may be considered that theprocessor 110 is implemented by using a special-purpose chip, aprocessing circuit, a processor, or a general-purpose chip.

In another implementation, it may be considered that the controllerprovided in this embodiment of this application is implemented by usinga general-purpose computer. To be specific, program code forimplementing functions of the processor 110 and the transceiver 130 isstored in the memory, and the general purpose processor 110 implementsthe functions of the processor 110 and the transceiver 130 by executingthe code in the memory.

For concepts, explanations, detailed descriptions, and other steps ofthe controller that are related to the technical solutions provided inthe embodiments of this application, refer to descriptions of thecontent in the foregoing method embodiments. Details are not describedherein again.

A person skilled in the art may understand that, for ease ofdescription, FIG. 7 shows only one memory and only one processor.Actually, a controller may include a plurality of processors andmemories. The memory may also be referred to as a storage medium, astorage device, or the like. This is not limited in this embodiment ofthis application.

It should be understood that, in this embodiment of this application,the processor may be a central processing unit (CPU for short), or theprocessor may be another general purpose processor, a digital signalprocessor (DSP for short), an application-specific integrated circuit(ASIC for short), a field programmable gate array (FPGA for short), oranother programmable logical device, a discrete gate or transistorlogical device, a discrete hardware component, or the like.

The memory may include a read-only memory and a random access memory,and provide an instruction and data to the processor. A part of thememory may further include a non-volatile random access memory.

In addition to a data bus, the bus may further include a power bus, acontrol bus, a status signal bus, and the like. However, for cleardescription, various buses are marked as buses in the figure.

In an implementation process, the steps in the foregoing methods can beimplemented by using a hardware integrated logical circuit in theprocessor, or by using an instruction in a form of software. The stepsin the methods disclosed with reference to the embodiments of thisapplication may be directly performed by a hardware processor, or may beperformed by using a combination of hardware and a software module inthe processor. The software module may be located in a mature storagemedium in the art, such as a random access memory, a flash memory, aread-only memory, a programmable read-only memory, an electricallyerasable programmable memory, or a register. The storage medium islocated in the memory, and the processor reads information in the memoryand completes the steps in the foregoing methods in combination withhardware of the processor. To avoid repetition, details are notdescribed herein again.

According to the methods provided in the embodiments of thisapplication, an embodiment of this application further provides asystem, including the foregoing controller, the foregoing ingressnetwork device, the foregoing egress network device, and a trafficanalyzer that may exist independently or may be integrated with thecontroller.

Sequence numbers of the foregoing processes do not mean executionsequences in various embodiments of this application. The executionsequences of the processes should be determined based on functions andinternal logic of the processes, and should not be construed as anylimitation on the implementation processes of the embodiments of thisapplication.

A person of ordinary skill in the art may be aware that, variousillustrative logical blocks (ILB for short) and steps described withreference to the embodiments disclosed in this specification may beimplemented by electronic hardware, or a combination of computersoftware and electronic hardware. Whether these functions are performedin a hardware or software manner depends on a specific application and adesign constraint condition of the technical solutions. A person skilledin the art may use different methods to implement the describedfunctions for each specific application, but it should not be consideredthat the implementation goes beyond the scope of this application.

In the several embodiments provided in this application, it should beunderstood that the disclosed system, apparatus, and method may beimplemented in other manners. For example, the described apparatusembodiment is merely an example. For example, the unit division ismerely logical function division and may be other division in actualimplementation. For example, a plurality of units or components may becombined or integrated into another system, or some features may beignored or not performed. In addition, the displayed or discussed mutualcouplings or direct couplings or communication connections may beimplemented by using some interfaces. The indirect couplings orcommunication connections between the apparatuses or units may beimplemented in electronic, mechanical, or other forms.

All or some of the foregoing embodiments may be implemented by usingsoftware, hardware, firmware, or any combination thereof. When softwareis used to implement the embodiments, all or some of the embodiments maybe implemented in a form of a computer program product. The computerprogram product includes one or more computer instructions. When thecomputer program instruction is loaded and executed on a computer, allor some of the procedures or the functions according to the embodimentsof this application are generated. The computer may be a general-purposecomputer, a special-purpose computer, a computer network, or anotherprogrammable apparatus. The computer instruction may be stored in acomputer-readable storage medium or may be transmitted from acomputer-readable storage medium to another computer-readable storagemedium. For example, the computer instruction may be transmitted from awebsite, a computer, a server, or a data center to another website,computer, server, or data center in a wired (for example, a coaxialcable, an optical fiber, or a digital subscriber line) or wireless (forexample, infrared, radio, or microwave) manner. The computer-readablestorage medium may be any usable medium accessible by a computer, or adata storage device, such as a server or a data center, integrating oneor more usable media. The usable medium may be a magnetic medium (forexample, a floppy disk, a hard disk, or a magnetic tape), an opticalmedium (for example, a DVD), a semiconductor medium (for example, asolid-state drive), or the like.

The foregoing descriptions are merely specific implementations of thisapplication, but are not intended to limit the protection scope of thisapplication. Any variation or replacement readily figured out by aperson skilled in the art within the technical scope disclosed in thisapplication shall fall within the protection scope of this application.Therefore, the protection scope of this application shall be subject tothe protection scope of the claims.

What is claimed is:
 1. A configuration method, applied to a network onwhich detection is performed by using a two-way active measurementprotocol (TWAMP), comprising: receiving, by a controller, a requestpacket sent by an ingress network device, wherein the ingress networkdevice is a network device through which a service flow flows into thenetwork, and the request packet comprises a destination IP address ofthe service flow; and determining, by the controller, based on thedestination IP address, that the service flow is an X2 service flow, andsending configuration information for TWAMP detection to the ingressnetwork device and an egress network device, wherein the egress networkdevice is a network device through which the service flow flows out ofthe network.
 2. The configuration method according to claim 1, whereinthe determining that the service flow is the X2 service flow comprises:searching for, by the controller based on the destination IP address, anegress device and a private network interface that correspond to thedestination IP address; and determining, by the controller, that theservice flow is the X2 service flow, in response to the controllerdetermining that the found egress device and the found private networkinterface are respectively an egress device and a private networkinterface that are obtained through mask matching.
 3. The configurationmethod according to claim 1, wherein sending the configurationinformation for the TWAMP detection to the ingress network device andthe egress network device comprises: forwarding, by the controller, therequest packet to the egress network device; in response to the egressnetwork device determining that the destination IP address correspondsto a virtual link (VLINK) route or an address resolution protocol (ARP)or a static route that is of the egress network device, receiving, bythe controller, a response packet sent by the egress network device;forwarding, by the controller, the response packet to the ingressnetwork device; and separately sending, by the controller, theconfiguration information for the TWAMP detection to the ingress networkdevice and the egress network device.
 4. The configuration methodaccording to claim 1, wherein the request packet, the response packet,and a configuration packet that carries the configuration informationuse a same packet format, and the same packet format comprises a rolefield, a message type field, a response value field, a source IP addressfield of the service flow, and a destination IP address field of theservice flow, wherein the role field indicates a role of a devicesending a packet, and the device role comprises the ingress networkdevice, the controller, and the egress network device; the message typefield indicates a message type, and the message type comprises therequest packet, the response packet, and the configuration packet; theresponse value field indicates whether the service flow is the X2service flow, and is valid in response to a value of the message typefield indicating a response packet; the source IP address field of theservice flow indicates a source IP address of the service flow; and thedestination IP address field of the service flow indicates thedestination IP address of the service flow.
 5. A configuration method,applied to a network on which detection is performed by using a two-wayactive measurement protocol (TWAMP), comprising: after a trafficanalyzer collects an ingress service flow of a first device and anegress service flow of a second device for analysis, and determines thatthe first device is an ingress network device through which a serviceflow flows into the network, and that the second device is an egressnetwork device through which the service flow flows out of the network,receiving, by a controller, a request packet sent by the trafficanalyzer, wherein the request packet comprises a first identifier and afirst interface of the ingress network device, a second identifier and asecond interface of the egress network device, and a source IP addressand a destination IP address of the service flow; and determining, bythe controller, based on the information in the request packet, that theservice flow is an X2 service flow, and sending configurationinformation for TWAMP detection to the ingress network device and theegress network device.
 6. The configuration method according to claim 5,wherein determining that the service flow is the X2 service flowcomprises: determining, by the controller, that the ingress networkdevice and the egress network device are bound to a same virtual routingforwarding; indicating, by the controller, the ingress network device todetermine whether the source IP address corresponds to a virtual link(VLINK) route or an address resolution protocol (ARP) or a static routethat is on the first interface, and indicating the egress network deviceto determine whether the destination IP address corresponds to a VLINKroute or an ARP or a static route that is on the second interface; inresponse to the ingress network device determining that the source IPaddress corresponds to the VLINK route or the ARP or the static routethat is on the first interface, receiving, by the controller, a firstresponse packet sent by the egress network device; in response to theegress network device determining that the destination IP addresscorresponds to the VLINK route or the ARP or the static route that is onthe second interface, receiving, by the controller, a second responsepacket sent by the egress network device; and determining, by thecontroller, that the service flow is the X2 service flow.
 7. Theconfiguration method according to claim 5, wherein the request packet,the response packet, and a configuration packet that carries theconfiguration information use a same packet format, and the packetformat comprises a role field, a message type field, a response valuefield, a source IP address field of the service flow, and a destinationIP address field of the service flow, wherein the role field indicates arole of a device sending a packet, and the device role comprises theingress device, the controller, and the egress device; the message typefield indicates a message type, and the message type comprises therequest packet, the response packet, and the configuration packet; theresponse value field indicates whether the service flow is the X2service flow, and is valid in response to a value of the message typefield indicating a response packet; the source IP address field of theservice flow indicates the source IP address of the service flow; andthe destination IP address field of the service flow indicates thedestination IP address of the service flow.
 8. A controller comprising:a transceiver, a memory, and a processor; the transceiver is configuredto cooperate with the processor to receive a request packet sent by aningress network device, wherein the ingress network device is a networkdevice through which a service flow flows into the network, and therequest packet comprises a destination IP address of the service flow;and the processor is configured to execute a computer-readableinstruction stored in the memory to: determine, based on the destinationIP address, that the service flow is an X2 service flow, and indicatethe transceiver to send configuration information for a two-way activemeasurement protocol (TWAMP) detection to the ingress network device andan egress network device, wherein the egress network device is a networkdevice through which the service flow flows out of the network.
 9. Thecontroller according to claim 8, wherein the processor is configured toexecute the computer-readable instruction to: search for, based on thedestination IP address, an egress device and a private network interfacethat correspond to the destination IP address; and determine that theservice flow is the X2 service flow, if the found egress device and thefound private network interface are respectively an egress device and aprivate network interface that are obtained through mask matching. 10.The controller according to claim 8, wherein the transceiver configuredto cooperate with the processor to: forward the request packet to theegress network device; receive a response packet sent by the egressnetwork device, wherein the response packet indicates that the egressnetwork device determines that the destination IP address corresponds toa virtual link (VLINK) route or an address resolution protocol (ARP) ora static route that is of the egress network device, forward theresponse packet to the ingress network device; and separately send theconfiguration information for the TWAMP detection to the ingress networkdevice and the egress network device.
 11. The controller according toclaim 8, wherein the request packet, the response packet, and aconfiguration packet that carries the configuration information use asame packet format, and the same packet format comprises a role field, amessage type field, a response value field, a source IP address field ofthe service flow, and a destination IP address field of the serviceflow, wherein the role field indicates a role of a device sending apacket, and the device role comprises the ingress network device, thecontroller, and the egress network device; the message type fieldindicates a message type, and the message type comprises the requestpacket, the response packet, and the configuration packet; the responsevalue field indicates whether the service flow is the X2 service flow,and is valid when a value of the message type field indicates a responsepacket; the source IP address field of the service flow indicates asource IP address of the service flow; and the destination IP addressfield of the service flow indicates the destination IP address of theservice flow.
 12. A controller comprising: a transceiver, a memory, anda processor; the transceiver is configured to cooperate with theprocessor to: receive a request packet sent by the traffic analyzer,wherein the request packet is received after a traffic analyzer collectsan ingress service flow of a first device and an egress service flow ofa second device for analysis, and determines that the first device is aningress network device through which a service flow flows into thenetwork, and that the second device is an egress network device throughwhich the service flow flows out of the network, wherein the requestpacket comprises a first identifier and a first interface of the ingressnetwork device, a second identifier and a second interface of the egressnetwork device, and a source IP address and a destination IP address ofthe service flow; and the processor is configured to execute acomputer-readable instruction stored in the memory to: determine, basedon the information in the request packet, that the service flow is an X2service flow, and indicate the transceiver to send configurationinformation for a two-way active measurement protocol (TWAMP) detectionto the ingress network device and the egress network device.
 13. Thecontroller according to claim 12, wherein the processor is configured toexecute the computer-readable instruction to: determine that the ingressnetwork device and the egress network device are bound to a same virtualrouting forwarding; and indicate the ingress network device to determinewhether the source IP address corresponds to a virtual link (VLINK)route or an address resolution protocol (ARP) or a static route that ison the first interface, and indicate the egress network device todetermine whether the destination IP address corresponds to a VLINKroute or an ARP or a static route that is on the second interface;wherein the transceiver is further configured to cooperate with theprocessor to: receive a first response packet sent by the egress networkdevice, wherein the first response packet indicates that the ingressnetwork device determines that the source IP address corresponds to theVLINK route or the ARP or the static route that is on the firstinterface, wherein the transceiver is further configured to cooperatewith the processor to: receive a second response packet sent by theegress network device, wherein the second response packet indicates thatthe egress network device determines that the destination IP addresscorresponds to the VLINK route or the ARP or the static route that is onthe second interface, the transceiver is further configured to andwherein the processor is further configured to execute thecomputer-readable instruction to determine that the service flow is theX2 service flow.
 14. The controller according to claim 12, wherein therequest packet, the response packet, and a configuration packet thatcarries the configuration information use a same packet format, and thesame packet format comprises a role field, a message type field, aresponse value field, a source IP address field of the service flow, anda destination IP address field of the service flow, wherein the rolefield indicates a role of a device sending a packet, and the device rolecomprises the ingress device, the controller, and the egress device; themessage type field indicates a message type, and the message typecomprises the request packet, the response packet, and the configurationpacket; the response value field indicates whether the service flow isthe X2 service flow, and is valid when a value of the message type fieldindicates a response packet; the source IP address field of the serviceflow indicates the source IP address of the service flow; and thedestination IP address field of the service flow indicates thedestination IP address of the service flow.